Effect

Generation III to IV

Block prevents the target from switching out. The effect only applies as long as the user is still in battle. The affected Pokémon can still switch out using Baton Pass, but in that case, the Pokémon that switches in will become trapped.

If the user switches out using Baton Pass, the effects of Block will still apply to the target. Also, if the target is Roared at or hit with a Whirlwind, they will still be switched out.

In the manga

In the Pokémon Adventures manga

Nosepass holds its arms out in front of it and releases a beam of energy from its body at the opponent, holding the opponent in place and preventing it from moving. The effects of the attack keeps going until Nosepass is knocked out.